A. Field of the Invention
The present invention relates to communications, and more particularly, to message encryption/decryption and authentication.
B. Related Art
Algorithms for protecting access to computing systems and for authenticating receipt of messages have been widely used in the past. Such algorithms often operate to authenticate and decrypt incoming messages and to generate authentication fields and encrypt outgoing messages. Importantly, although the algorithm used to encrypt and/or authenticate a message can be widely known, a secret keying variable should provide sufficient protection so that unwanted access to a system can be prevented.
Encryption algorithms typically turn plain text into cipher text. The algorithm preferably is "reversible" so that cipher text can be returned to plain text. Plain text, as used herein, refers to the data/messages in a form used by other components of a system.